Integrated electronic modules can be used to perform a variety of functions. For example, such modules can include one or more passive components and interconnections, such as to provide a single unitized module assembly that can placed upon a printed circuit board assembly. Such a module can include circuits for performing various functions, such as providing a passive filter, for example, or for providing more complex functionality, such as including one or more monolithic integrated circuits or active devices. A monolithic integrated circuit can include one or more of active devices such as transistors, or passive devices such as resistors, inductors, or capacitors, and interconnections. Such a monolithic integrated circuit can be fabricated upon or include a semiconductor substrate. Limitations can exist with respect to a magnitude of passive component values that can be implemented using a monolithic integrated circuit. Accordingly, in certain applications, a monolithic integrated circuit can be coupled to one or more components located “off-chip,” but such components may still be included within the integrated electronic module package.
In one illustrative application, a monolithic integrated circuit can include a power supply controller circuit such as including one or more of analog or digital circuitry forming a portion of a regulated power supply. A combination of the integrated circuit and other off-chip components can provide a regulated power supply circuit. Components separate from the integrated circuit can include an energy storage element (e.g., an inductor), and other circuitry such as one or more large bypass capacitors or power switching devices (e.g., power transistors). Use of bypass capacitors may still result in undesired levels of output ripple (e.g., output voltage variation or noise deviating from the nominal regulated output voltage) under a variety of load conditions. Accordingly, different techniques can be used to provide filtering or suppression of ripple. In one approach, a tuned filter circuit can be used to attenuate ripple, such as having a stop band corresponding to a fundamental frequency of the ripple signal.